zrs70,

I have no answer to your question, but I do share in your pain.

For my trip later this week: ORD-NRT-PVG-ORD, I tried to use that same "Stopover Freebie" rule for my C-class ticket. I need to stop in Tokyo for the night to meet a colleague...so I wanted to continue on to PVG the next day (on the natural UA flight that one has to connect to at NRT from ORD).

Nope. UA tells me that even with a full-fare C-class ticket, I cannot stop for more than 24 hours. This stopover will be approximately 26 hours. No flexibility here. The ticket price, as you mentioned, jumps considerably when they book one segment to NRT and then a second segment to PVG.

I hope someone has an answer for us...I'd love to be able to take advantage of these relatively cheap C-class tix to PVG from the US.